Powered roller curve



Julie 9 D. A. SCHNEIDER ETAL 18 POWERED ROLLER CURVE Filed Dec. 21, 1962 2 Sheets-Sheet; 1

lll

WWW

INVENTORS 614A; FALCON 00mm 4. saw/05 AWFMEKS I June 15, 196.5 D. A. SCHNEIDER ETAL POWERED ROLLER CURVE 2 Sheets-Sheet 2 Filed Dec. 21, 1962 INVENTORS CARA J. l-AZCO/V 00/1/1410 A SCI/M905? United States Patent 3,189,161 POWERED RQLLER CURVE Donald A. Schneider, Ada, and Carl J. Falcon, Grand Rapids, Mich, assignors to The Rapids-Standard Company, Inc, Grand Rapids, Mich, a corporation of Michigan Filed Dec. 21, 1962, Ser. No. 246,396 Claims. (Cl. 198-127) This invention concerns powered roller curves in conveyors, and more particularly the drive means for driving the rollers of the powered curve.

Providing an effective driving mechanism for curved sections of live roller conveyors has long been a problem of great interest in the conveyor art. Previous attempts at providing drives for powered curves have involved the use of gear trains or chain drives with sprockets on each roller, all of which are expensive, noisy, and require much lubrication, or V-belts running on curved guides which wore out at a ratethat caused serious maintenance difliculties. It was thereupon proposed to provide a chain running in a horizontal plane, Whose links were provided with weights-running on the top surface of the tapered rollers of the curve and depending on their own weight to provide sufficient frictional contact with the rollers. This system had the disadvantage of requiring extra width on the conveyor both for taking care of the return run of the chain, and for providing sufficient room for the weights 7 to engage the tapered rollers along their top surface.

The present invention makes it possible to drive the conveyor from the underside with a chain drive which transmits its movement to the underside of the tapered rollers through a series of resilient blocks which can be pressed against the rollers with any desired amount of pressure and which can be made to merge into one another to the point of eliminating troublesome ripple and vibration. In another embodiment of the invention particularly adapted to curves whose curvature is on the order of 180", the chain is indeed guided in a horizontal plane, but firm engagement between the driving means and the rollers is maintained by compressing the resilient blocks between a turntable and the underside of the rollers to maintain a constant pres-sure on the rollers.

It is therefore the object of this invention to provide a durable, three-dimensionally flexible drive for a powered roller curve for live roller conveyors.

It is a further object to provide a drive of the type described which accomplishes its function without imparting to the rollers of the curve any undesirable ripple or vibration.

It is still another object of this invention to provide a drive of the type described in which the frictional contact between the drive means and the roller-s can be maintained consistently at any desired pressure throughout the entire extent of the curve.

It is sti-ll another object of this invention to provide a drive means for the described purposes which can be used interchangeably either in a horizontal or a vertical position.

These and other objects of this invention will become apparent from a perusal of the following specification, taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective side view of a powered roller curve constructed in accordance with this invention;

FIG. 2 is a detail of .a portion of FIG. 1 with the rollers of the curve removed so as to show the drive mechanism;

FIG. 3 is a vertical section through the radially outer portion of the curve along a plane perpendicular to the direction of travel of the goods;

FIG. 4 is a plan view of a 180 curve constructed in 3,189,161 Patented June 15, 1965 accordance with an alternative embodiment of the invention;

FIG. 5 is a vertical section along line VV of FIG. 4;

FIG. 6 is a perspective view of a drive block;

FIG. 7 is a plan View of the same drive block; and

FIG. 8 is a vertical section along line VIII-VIII of FIG. 7.

Basically, the drive of this invention consists of a threedimensionally flexible chain drive in which the sliding fricton of the mechanism against stationary parts is car ried by metallic and lubriccus surfaces while the rolling friction of the drive against the rollers is carried by resilient elements having a high coefficient of friction.

The alternative embodiment in which the chain is in a horizontal plane eliminates, according to this invention, all sliding friction between the drive and stationary elements and leaves only the friction between the drive and rolling elements. In each instance, adjustment of the frictional pressure is possible by the vertical adjustment of supporting elements and is in no way dependent on the weight of any particular member of the driving mechanism.

Referring now to the drawings, FIG. 1 shows the powered curve Ill to consist essentially of a pair of channelshaped frame members 12, 14 in which are journaled a plurality of tapered rollers 16 whose diameter radially outward of the curve is greater than their diameter radially inward of the curve, The rollers 1-6 are driven by a drive mechanism powered by a motor 18 which drives a sprocket wheel 2%) over which is entrained a chain 22 whose links are provided with resilient drive blocks 24 (FIG. 2).

As Will be more clearly seen from FIG. 3, the drive mechanism is supported on a mounting plate 26 attached in any convenient manner to a support bracket 28 attached to the cross members .36 (FIG. 2). As will be best seen in FIGS. 1 through 3, the mounting plate 26 is curved about the same axis as the powered roller curve itself. It will be understood that although the drive mechanism has been shown along the outward end of the rollers 16, it is equally possible without any changes in the device to position the drive mechanism under the center of the rollers, which makes possible an S configuration of the powered roller curve, as will presently be :seen. Fastened to the mounting plate 26 in a rub rail 32 of a lubricous material such as nylon. As will be readily seen in FIG. 3, the metallic links 34, 36 of the chain 22 rub against the rub rail 32 as the chain curves to the left in FIG. 3. Due to the l-ubricous nature of the nylon rail and the ability of the metal links to carry lubricants, there is very little wear between the rub rail 3-2 and the links 34, 36. Furthermore, the resilient nature of the nylon effectively reduces any noise caused by the friction of the chain 22 against it.

Radially outwardly of the rub rail 32 is a riding rail 38 on which the rotatable sleeves 40 of the links 36 roll. The riding rail 38 provides vertical support for the driving run of the chain 22 (links 36), and its vertical adjustment determines the pressure with which the resilient drive blocks 42 are pressed against the underside of the rollers 16.

On the return run of the chain (links 34), the chain mechanism is vertically supported by rolling engagement of the resilient drive blocks 44 with the supporting rollers 46 journaled in the mounting plate 26.

It will be readily seen that the symmetry of the mechanism about a vertical axis is such that the rub rail 32 may equally well be positioned on the left-hand side (inFIG. 3) of the chain 22 if the chain curves toward the left, as on the right-hand side of chain 22 if the chain 22 were to curve to the right. This is the feature which enables the curve to be built in the form of an S.

In such a case, the drive mechanism would be so positioned that the drive blocks 42 are under the center of rollers '16, and in the first pontion of the S, the mounting plate 26 and rub rail 32 may for example be on the left side of the chain, whereas in the second portion of the S, they would be on the right side of the chain. It is thus possible to drive the entire S curve with a single chain; a feat impossible with the drive mechanisms previously known.

Turning now to FIG. 4, it will be seen that in this alternative embodiment, the curve once again consists of an inner frame member 14 (not shown) and an outer frame 12 between which are mounted tapered rollers 16. A motor 18 is again provided to drive a sprocket wheel 20 about which is entrained a chain 22. In this embodiment, however, the chain runs in a horizontal plane. Following the chain 22 in a clockwise direction, it wi l be noticed that it is entrained over an idler sprocket 52 and thence underneath the inner edge of the conveyor to point 54 where the radially inwardmost portion of the chain engages the flange 56 of a turntable 58 journaled on an axle 6t and supported at its circumference by rollers 62. As is more apparent in FIG. 5, the blocks 24 are supported by the annular lip 64 of the turntable 58 and are pressed against the underside of the rollers 16. Thus, adjustment of the pressure of blocks 24 against roller 16 is possible by raising or lowering the turntable 58. It will be noted that within the region of the curved portion of the conveyor 50, there is no relative motion between the chain 22 or the blocks 24 and the turntable 53.

Referring now to FIGS. 6 through 8, the resilient block 24, in its preferred but not absolutely necessary form, is seen to be generally arrow-shaped. In this preferred embodiment, the block 24 has a cylindrical upper surface 79 and fiat sides "/2, 74. The purpose of the cylindrical top surface 76 is to eliminate chain instability by causing the contact between the block 24 and the conveyor rollers 16 to occur at an inclined portion of the block surface. This arrangement avoids tilting of the block 24 by the non-horizontal bottom surface of the tapered roller.

The sides 72, 74-, on the other hand, are fiat because as will be seen in FIG. 5, the side 72 in the alternative embodiment of the device is flatly supported by the turntable S8 and consequently does not show a tendency to wobble, particularly since, as has been previously described, there is no relative motion between the turntable 53 and the chain 22 or blocks 24.

The arrow-like configuration of the blocks 24 serves two purposes: for one, as is most clearly shown in FIG. 2, the point of each block engages the tail of the preceding block during the driving run and thus holds the blocks in reasonably steady alignment with one another. Furthermore, as the blocks pass under any one of the rollers 16, the pressure of the roller is gradually transferred from one block to the next, i.e. the roller is already supported by the point of the following block before the tail of the preceding block disengages the roller surface. This results in a more ripple-free and vibrationless operation with a considerable reduction of noise over blocks whose leading surface is perpendicular to their direction of motion.

In order to permit the mechanism of this invention to be interchangeably used in a ho izontal plane or in a ver tical plane, the sides 72, 74 are diamond-shaped as best shown in FIGS. 6 and 7. In other words, edge 80 makes an acute angle with edge 82 and an obtuse angle with edge Edge as is parallel to edge 86, and edges 82 and 84 are of course also parallel. This configuration permits gradual transfer of the rollers from one block to the next regardless of whether the blocks 24 are used in a vertical plane or in a horizontal plane.

It will be understood in connection with the description of FIGS. 6 through 8 that instead of having a pointed nose, the block 24 may equally well have a round nose or a straight nose cut at angle to sides 72, 74-; or any other configuration which permits gradual transfer of the roller load from one block to the next. Likewise, the sides 7? '74 need not be diamond-shaped if the blocks 24- are not to be used in the horizontal embodiment of FIG. 4, or vice versa.

Preferably, the blocks 24 are made of a rubber-like resilient material such as neoprene, which has a high coefficient of friction, is highly wear-resistant, and is impervious to the lubricants used to lubricate the links of the chain and the rub rail 32.

It will be seen that the present invention provides a versatile, simple, and effective drive means for powered roller curves which has been empirically shown to be far superior to known devices of similar purpose in both initial expense and maintenance cost as well as quietness and reliability. It will therefore be understood that the basic concepts of this invention can be carried out in many different forms, of which the embodiments shown and described are merely illustrative. It is therefore to be understood that the present invention is not to be deemed limited by the embodiments shown, but only by the scope of the following claims.

We claim:

1. A nonlinear live roller conveyor having live rollers; an endless chain; means for driving said chain; support means for supporting said chain against vertical movement at a predetermined spacing from said live rollers of said conveyor; lateral guide means for supporting said chain against radially inwardly movement; resilient, independently movable drive blocks mounted on links of said chain, said live rollers of said conveyor being in frictional engagement with said drive blocks; and said blocks shaped such that they laterally overlap one another, whereby one or more of said blocks engages any one of ie rollers at all times.

2. The device of claim 1, in which said lateral guide means include member of lubricous material of such dimensions as to frictionally engage the side of said links but remain spaced from said blocks.

3. The device of claim 1, in which said chain links include rotatable parts, and said support means include track means for supporting said rotatable parts of said chain in rolling relation.

4. A live roller conveyor having live rollers; an endless chain; means for driving said chain; fixed support means supporting the links of said chain on the driving run underneath and at a predetermined spacing from said live rollers of said conveyor; resilient, independently movable drive blocks mounted on links of said chain, said live rollers of said conveyor being in frictional engagement with said drive blocks; said blocks shaped such that they laterally overlap one another, whereby one or more of said blocks engages any one of the rollers at all times; and rotatable support means engaging said blocks on the return run to support said chain during the return run.

5. The device of claim 4, in which said conveyor is nonlinear, further comprising fixed means of lubricous material so positioned and dimensioned as to frictionally engage the side of said links to hold them against radially inward movement during both the driving run and the return run, said last-named means being spaced from said blocks on both the driving run and the return run.

6. A live roller conveyor having live rollers; an endless chain; means for driving said chain; resilient, independently movable drive blocks mounted on links of said chain, said live rollers of said conveyor being in frictional engagement with said drive blocks, and said blocks being of a shape such that the space between the roller-engaging surfaces of adjacent blocks is disposed at an angle to the block-engaging line of the surface of the roller, said space being sufficiently small that said roller engages the rollercngaging surface of one of said blocks before leaving that r of the preceding block.

, tional engagement with said drive blocks, said blocks being of a shape such that throughout the driving run, the perimeter of the leading side of one block is immediately adjacent and parallel to the perimeter of the trailing side of the preceding block, the top and side portions of each of said perimeters being inclined with respect to a vertical plane normal to the direction of motion of the chain on the driving run, whereby gradual transfer of each roller from one block to, the next is accomplished regardless of whether the roller engages the top surface or a side surface of said block.

8. A nonlinear live roller conveyor having live rollers; a vertically adjustable curved mounting plate coaxial with said nonlinear conveyor; an endless chain running in a vertical loop on sprockets fixed to said mounting plate; motor means for driving said sprockets; each link of said chain carrying a pair of fixed mounting ears and a pair of rotatable sleeves; a drive blockof resilient, Wear-resistant, lubricant-impervious material fixed to said mountting ears on each of said links; said blocks shaped such that they laterally overlap one another, whereby one or more of said blocks engages any one of the rollers at all times; curved track means coaxial with said conveyor attached to said mounting plate, said sleeves rolling on said track means to vertically support said chain; a curved guide plate of lubricous material coaxial with said conveyor supported on said mounting plate adjacent said said rollers of said conveyor being in frictional engagement with the top surfaces of said blocks on the driving run, and said top surfaces being convex.

9. A nonlinear live roller conveyor having live rollers; an endless chain disposed in a horizontal plane; means for driving said chain; guide means for guiding said chain through a nonlinear path paralleling said conveyor; rcsilient, independently movable drive blocks mounted on links of said chain, the underside of said live rollers of said conveyor being in frictional engagement with said drive blocks; said blocks shaped such that they laterally overlap one another, whereby one or more of said blocks engages any one of the rollers at all times; and support means engaging one side face of said blocks at a spacing from said live rollers of said conveyor such that the other side face 'of said blocks is pressed against said rollers with a predetermined pressure.

10. The device of claim 9, in which said nonlinear con veyor has at least a portion of substantially constant radius, and said support means includes a'turntable coaxial with said portion, said turntable having a horizontal portion supporting said blocks, and a vertical flange radi ally inwardly of said horizontal portion which constitutes said guide means. 7

References Cited by the Examiner UNITED STATES PATENTS 1,845,297 2/32 Lathrop 198-189 1,967,747 7/34 Eggleston 198l27 2,419,321 4/47 Lopes 198189 2,792,928 5/57 Holz 198-l89 2,866,538 12/58 Goldberg 198l89 3,040,872 6/62 Hohl 198127 FOREIGN PATENTS 885,828 12/61 Great Britain.'

SAMUEL F. COLEMAN, Primary Examiner. ERNEST A. FALLER, JR., Examiner. 

1. A NONLINEAR LIVE ROLLER CONVEYOR HAVING LIVE ROLLERS; AN ENDLESS CHAIN; MEANS FOR DRIVING SAID CHAIN; SUPPORT MEANS FOR SUPPORTING SAID CHAIN AGAINST VERTICAL MOVEMENT AT A PREDETERMINED SPACING FROM SAID LIVE ROLLERS OF SAID CONVEYOR; LATERAL GUIDE MEANS FOR SUPPORTING SAID CHAIN AGAINST RADIALLY INWARDLY MOVEMENT; RESILIENT, INDEPENDENTLY MOVABLE DRIVE BLOCKS MOUNTED ON LINKS OF SAID CHAIN, SAID LIVE ROLLERS OF SAID CONVEYOR BEING IN FRICTIONAL ENGAGEMENT WITH SAID DRIVE BLOCKS; AND SAID BLOCKS SHAPED SUCH THAT THEY LATERALLY OVERLAP ONE ANOTHER, WHREBY ONE OR MORE OF SAID BLOCKS ENGAGES ANY ONE OF THE ROLLERS AT ALL TIMES. 